The present invention relates exclusively to the field of mailing systems and more particularly to document feeders.
Modules for feeding mailing machines, or feeders, are well known. In addition to the rollers for selecting and gripping documents and the conveyor rollers, such feeders all comprise a system for ensuring suitable positioning of the mailpieces with a view to being gripped by the document selection and gripping rollers. Such positioning may be effected via the rear of the mailpiece, as disclosed in U.S. Pat. No. 5,203,263 to ASCOM and in which FIG. 1 illustrates a rear aligning device, or wedge, 16. It may also be effected from the side. U.S. Pat. No. 4,956,782 to PITNEY BOWES discloses a mailing assembly of which the feeder module comprises a lateral aligning device, or guide, 53 to apply the mailpieces against a registration wall 59.
These lateral and rear aligning devices used alone in the afore-mentioned documents might very certainly also be used in combination to guide the mailpieces more precisely, in particular towards a franking station in the mailing machine disposed downstream of the feeder.
The rear aligning device generally slides in a longitudinal groove parallel to the direction of advance of the mailpieces, while the lateral aligning device generally slides in a transverse groove perpendicularly to said direction of advance and to the wall for registration of these pieces.
However, neither of these solutions takes into account the different formats of mailpieces capable of being positioned and guided in a conventional feeder module. Now, such positioning is particularly delicate, as:
for large formats, the zone of contact between pieces and aligning device may be considerably off-centred with respect to these pieces; this may falsify the alignment of these pieces with respect to the registration wall,
for small formats, the lateral aligning device tends to abut on the rear aligning device without being able suitably to perform its function of aligning; in effect, taking into account the longitudinal groove, the rear aligning device requires a certain space necessary for efficient guiding and decollation, which is generally incompatible with the smallest formats.
In addition, with the increasing development of digital franking machines, particularly employing ink jet, the crucial problem is raised of the highly precise positioning of the mailpiece in order to obtain a print of sufficient quality, any defective positioning and/or guiding in the feeder module running the considerable risk of the franking station printing indicia of unacceptable monetary quality.
It is an object of the present invention to provide an aligning device for a document feeder in a mailing machine, which allows a suitable aligning of the mailpieces of small and large formats, with rear and lateral aligning elements of reduced size. Another object of the invention is to effect such positioning rapidly and facilitating extraction of the lower pieces (with respect to a stack of mailpieces). A further object of the invention is to make it possible to take into account mailpieces of large, non-standard formats, in particular of a format larger than the width of the feeder.
These objects are achieved by an aligning device for a feeder of a mailing machine, comprising a first rear aligning guide mobile in a direction of advance of the mailpieces and a second lateral aligning guide mobile in a direction perpendicular to this direction of advance, each aligning guide being displaceable in a respective groove, characterized in that the groove associated with said rear aligning guide is inclined by a determined angle xcex1 with respect to said direction of advance of the mailpieces, with the result that said rear aligning guide remains substantially centred on the mailpiece whatever the format of this piece.
In this way, off-centering of the rear guide for the large-format mailpieces is avoided and it becomes possible to align the small- and large-format pieces suitably in median zone.
According to a preferred embodiment, the rear aligning guide presents the form of a wedge comprising at least two successive slopes, a first slope of slight inclination and a second slope of steep inclination, and preferably presenting three slopes with an additional slope of average intermediate inclination. The first slope of slight inclination ensures support of the mailpieces while the second slope of steep inclination facilitates the extraction one by one (singulation) of these pieces.
The rear aligning guide may advantageously also comprise a mark intended to be aligned with one of a plurality of marks previously engraved on the tray for receiving the mailpieces and each corresponding to a standard format of mailpieces. Thanks to such marking, it is thus possible to ensure rapid positioning of the rear guide as a function of the stack of mailpieces having to be positioned on the tray. It may also comprise two gauge labels marking two determined threshold thicknesses of the mailpieces each corresponding to a determined operation of adjustment of the feeder. By this configuration of marking, a simple visual detection of thickness with respect to these two marked thresholds is sufficient to adjust this feeder in order to process batches of mailpieces of the corresponding range of thicknesses.
According to a preferred embodiment, the rear aligning guide comprises a lower longitudinal member provided with at least one elastic element intended to cooperate with a cavity made in the longitudinal groove, so as to define a position of stop for this guide.
The lateral aligning guide advantageously slides in the lateral groove associated therewith via a slideway. With this structure, it is possible to align mailpieces whose dimensions in width are greater than that of the tray for receiving these pieces.
The lateral aligning guide comprises a lower longitudinal member provided with at least one first elastic element adapted to cooperate with a cavity made in said slideway, so as to define a position of stop for this guide, and the slideway is provided with at least one second elastic element adapted to cooperate with a cavity made in the transverse groove, so as to define a position of stop for this slideway.
In order to allow a differential displacement of the slideway and of the longitudinal member, the elasticity of the second elastic element is less than that of the first elastic element.
According to a particular form of embodiment, the lateral aligning guide may comprise a system for automatically adjusting its positioning, as a function of the width of the mailpiece, comprising at least one position and/or pressure sensor fixed on an end part of the lateral aligning guide in order to control displacement of a drive motor under the action of a control circuit. Alternately, this automatic adjusting system may also comprise a system of calibrated springs in order to maintain a substantially constant optimal clearance between an end part of the lateral aligning guide and a stack of mailpieces registered against the wall.